Organic polybasic acid polyesters of hydroxydihydronorpolycyclopentadienes



Patentedov. 5, i946 ORGANIC POLYBASIC ACID POLYESTER/S 0FHYDROIHYDRGNORPQLYCYCLO- TENTADIENES Herman A. Bruson, Philadelphia,Pa., assignor to The Resinous Products & Chemical Company, Philadelphia,Pa, a corporation of Delaware No Drawing. Application March 13, 1944,Serial No. 526,313

6 Claims. (Cl. 260-475) organic poiycarboxylic acid, advantageously inthe presence of an acidic condensing agent such as boron trifluoride, asdescribed in copending application Serial No. 476,639, filed February20, 1943, of which the present application is a continuation-in-part,whereby addition of each carboxyl group to the endomethylene cycle ofthe dicyclopentadiene is accompanied by a simultaneous molecularrearrangement of the latter to the nordicyclopentadienyl ring system,thus:

mooon). +1

ca ms CH wherein R is the organic residue of a polycarboxylic acid and nis an integer of at least two. The first formula given for the productsis more probable, difiering from the second only in the position of thedouble bond of the terminal cyclopenteno group relative to the positionof the mnt products of a polycarboxylic acid and dicyclopentadiene. Theyare esters of hydroxydihydronordicyclopentadiene and a polycarboxylicacid and have the general formula:

0 Z on-l Coo H il 1 wherein, as before, R is the organic residue of apoiycarboxylic acid, 11. is a small integer of two or more, and Cal-I4is a propylene group which in conjunction with the adjoining carbonatoms forms a cyclopenteno group. The functional carboxyl group isattached tothe dihydronordicyclodienyl ring system at a secondary carbonatom flanked by a methylene group and by a tertiary carbon atom in anendoethylene cyclopentano group which carries the said propenylene.group forming a cyclopenteno ring therewith.

Theaddition of a polycarboxylic acid to dicyclopentadiene having'twodouble bonds and one endomethylene cycle per molecule occurs readily attemperatures from about C. to about C., although temperatures bothsomewhat higher and lower may be used. It is sometimes desirable, butnot essential, to use an organic solvent, such as benzene, toluene,xylene; ethylene dichloride, or

other organic solvent, in which case the reaction may be effected underreflux.

Small amounts of acidic condensing agents promote the formation of thedesired polyesters. The most efi'ective are boron trifiuoride and itsvcoordination complexes, such as those formed with boron trifluoride andoxygenated compounds, including aldehydes, ketones, ethers, esters,alcohols, and carboxylic acids, typified by BF3.2CH3CHO,BF3.C2I-I5OC2H5, BF: .CHaCOOCzI-Is, BFs.CH3CQCH3, BFaCiI-l'sOH etc. Thecatalyst may be removed from the reaction mixture by washing with wateror mildly alkaline solutions,

such as aqueous sodium carbonate solutions.

The reaction product may bedried with-conventional drying agents, orwater may be removed therefrom by distillation of a solvent. The productmay be further purified by treatment with activated clays or charcoaland/or distillation functional substituent in the opposite terminalcycle, an endoethylene cyclopentano group.

The products as thus obtained may be regarded from one point of view asaddition-rearrangeunder reduced pressure in many cases.

The compounds formed are esters from one molecule of an organicpolycarboxylic acid and at least two molecules ofhydroxydihydronordicyclopentadiene.

Another method is to esterify one molecule of the organic polycarboxylicacid or its anhydride with at least two molecules ofhydroxydihydronordicyclopentadiene, a new alcohol obtained by of whichmay be represented as follows: I

Hydroxydihydronordicyclopentadlene may thus be represented by theformula:

wherein C3114 is a propenylene group which in conjunction with theadjoining carbon atoms .4 admixed with at least one oxidation catalyst.The oxidation catalysts include peroxides, such as benzoyl peroxide,tert. butyl hydroperoxide, or lauroyl peroxide, and metallic driers,such as the oil-soluble salts of heavy metals, typified by lead, cobalt,manganese, and other polyvalent metals supplying siccative action, andof carboxylic acids imparting oil-solubility to the salt, in-

forms a cyclopenteno group as one terminal cycle.

Still another method for the preparation of the esters of this inventionis based upon transesteriiication or ester interchange. According tothis method, an ester :of a polycarboxylic acid and an alcohol of lowermolecular weight than hydroxydihydronordicyclopentadiene is heated withhydroxydihydronordicyclopentadiene in the presence of a catalyst, suchas sodium ethylate or sulfuric acid, and the alcohol of lower molecularweight displaced. Thus, by displacing at least two molecules of a lowermolecular weight alcohol with hydroxydihydronordicyclopentadiene, theremay be prepared polyesters of said acid and said compound which containonly these components or which contain these components in addition toanother alcoholic residue or other alcoholic residues.

Particularly useful polyesters are derived from carbonic, oxalic,malonic, succinic, maleic, fumaric, chloromaleic, glutaric, e,a-diethy1glutaric, itaconic, adipic, pimelic, suberic, azelaic, sebacic,phthalic, 3,6 endomethylene-1,2,3,6-tetrahydrophthalic, A-tetrahydrophthalic, tartaric, malic', citric, and tricarballylic acids.Esters may also be prepared from other polycarboxylic acids, such as'v-alkyl-v-carboxypimelic acids, delta-ketonic eluding naphthenic acids,long-chained fatty acids such as .linolelo and linolenic, and etheracids, such as butoxyacetic or octyloxyacetlc acids. Mixtures ofperoxides and metallic driers are particularly efiicacious.

When coating compositions comprising the polyesters of this inventionand an oxidation catalyst are applied to surfaces which are then exposedto air or preferably baked at 130 C. to 190 (3., they are converted tohard, tough films, which are substantially insoluble in all commonorganic solvents and are highly water-resistant and nonporous. When usedin finishes on metal, exceptional adhesion is obtained, and treatedmetal sheets finished with a baked coating may be flexed withoutcracking or breaking of the film.

Since the new esters are compatible with nitrocellulose as well as withthe natural drying oils, for example, linseed, tung, soyabean, oiticica,and fish oils, as well as with many natural and synthetic resins, theymay be used for the preparation of a wide variety of coating and plasticcompositions.

The following examples illustrate the preparation and properties ofthese esters:

Example 1 Fifty-nine grams of diethyl carbonate was mixed with 150 gramsof hydroxydihydronorcyclopentadiene and one gram of sodium was added.

. pressure was then reduced and distillation contetracarboxylic acids(of. United States Patent 2,329,432) and the carbocyclic compounds inwhich two to six p-carboxyethyl groups are joined to unsaturatedcarbocycles (cf. United States Patent No. 2,339,218)

The new esters are advantageously used as vehicles in preparingpaintsyvarnishes, and similar coating materials. For this purpose, theymay be tinues until no more ethyl alcohol was obtained. Thereupon, thestill residue was distilled under reduced pressure. The fraction boilingbetween 200 and 240 C. at 3 mm. was a pale yellow viscous oil, amountingto 61 grams, which upon re- Its distillation boiled at 217-220 C./2.5mm. analysis agreed with the formula for di-(dihydronordicyclopentadienyl) carbonate,

It possessed the following constants: N 1.5288; d4 1.0216.

The above ester was mixed with such amounts Example 2 A mixture of 36.5grams of adipic acid, grams of hydroxydihydronordicyclopentadiene, 120

grams of benzene, and 0.5 gram of sulfuric acid was stirred and boiledunder a'reflux condenser attached to a water trap for six hours until nomore water distilled over with the benzene. The product was cooled,washed several times with cold water, then with dilute sodium carbonatesolution, followed by a water wash. The benzone was evaporated ed andthe excess hydroxydihydronordicyclopentadiene distilled oil in vacuo. 1

The residual oil consisted essentially of di-(dihydronordicyclopentadienyl) adipate,

CH13OCOCH2CH2CH2CH2COOC10H13 Upon distillation in high vacuo, it boiledbetween 250 and 270C. at 3 mm. and formed a pale yellow oil whichcrystallized on standing. After recrystallization from ethanol, itformed colorless crystals melting at 75-77." C.

A solution of the above ester in benzene was mixed with lead, cobalt,and manganese naph thenates to give a composition containing 0.25% oflead, 0.02% of cobalt, and 0.02% of manganese on the weight of theester. A film of this solution was baked on a steel panel for one hourat 150 C. to yield a hard, varnish-like coating.

Ewample 3 A mixture of 180 grams of hydroxydihydronordicyclopentadiene,59 grams ofsuccinic acid, 200 grams of benzene, and one gram of sulfuricacid (95%) was boiled under a reflux condenser attached to a water trapfor six and one-half hours, at which tim 18 grams of water had beencollected. The product was then cooled and mixed with ten. grams ofcalcium hydroxide. This mixture was stirred for several hours andfiltered. The filtrate was evaporated to dryness. The product,consisting essentially of di-(dihydronordicyclopentadienyl) succinatecrystallized on standing. After recrystallization from methanol, itformed colorless crystals melting at 100 C.

Example 4;

(a) A mixture of 66 grams oi dicyclopentadiene, 22.5 grams of anhydrousoxalic acid, and

75 grams of tetrachlorethane was stirred and yield was '75 grams.

(b) A mixture of 126 grams of oxalic acid dihydrate, 380 grams ofhydroxydihydronordicyclopentadiene, 200 grams of benzene, and one gramof 98% sulfuric acid was stirred and boiled under a reflux condenserattached to a water trap. At the end of three and one-half hours ofboiling, '74 cc. of water had been separated in the trap, indicatingthat the esterification was complete. The product was cooled to roomtemperature and stirred for a half hour with ten grams of powderedcalcium hydroxide and five grams of water to destroy free acidity. Theprecipitate which was formed was filtered off and the filtrat heated invacuo up to a vapor v Example 5 A mixture of 49 grams of maleicanhydride, grams of benzene, 302 grams ofhydroxydihydronordicyclopentadiene, and 1.5 grams of concentratedsulfuric acid was boiled under a reflux condenser attached to a watertrap for three hours, during which time 8.5 grams of water was collectedin the trap. The reaction product was cooled to room temperature andstirred for several hours with five grams of powdered calcium hydroxide.The mixture was filtered and the clear filtrate distilled at 3 mm. untilthe benzene and excess hydroxydihydronordicyclopentadiene had beenstripped oil.

The residual product, consisting of di-(dihydronordicyclopentadienyl)maleate,was a thick oil. When heated in the air at 190-200 C., itrapidly polymerizes to a hard re'sin.- Films of the oil dry by oxidationin the air.

A solution of equal parts of the above ester and linseed oil was mixedwith 0.50% of lead, 0.02% of cobalt, and 0.02% of manganese in the formof the corresponding naphthenate driers, and films of this solutionbaked on steel plate at 150 C. forone to two hours. Hard, adherent,tough, mar-proof coatings were obtained.

Example 6 A mixture of 178 grams of sebacic acid, 531 grams ofhydroxydihydronordicyclopentadiene, grams of ethylene dichloride, and1.5 grams of concentrated sulfuric acid was boiled for two hoursunder areflux condenser attached to a water trap until 33 cc. of water had beencollected. The product was cooled, stirred for two hours with five gramsof powdered lime, filtered, The

excess of the alcohol used. The final product was a thick oil consistingessentially of di-(dihydronordicyclopentadieneyl) -sebacate.

A solution was prepared by ,mixing this ester with driers to give acomposition containing 0.5% of lead, 0.03% of cobalt, and 0.03% ofmanganese in the form of their naphthenates. A film of this solution wasformed on a steel plate and baked for two hours at -150 C. A hard,tough, adherent, mar-proof film of excellent quality was thus obtained.

In the same manner as described in Example 6. the phthalic acid ester ofdihydronordicyclopentadienyl phthalate is obtained as a thick oil byusing grams of phthalic anhydride in place of the sebacic acid. Whenmixed with driers as described above, it gives a hard film when bakedfor two hours at 150 C.

The corresponding tartaric acid, tricarballylic acid, citric acid,3,6-endomethylene-1,2,3,6-tetrahyd'rophthalic acid polyesters ofhydroxydihydronordicyclopentadiene can be similarly prepared. They arethick, autoxidizable, polymerizable oils useful for the preparation ofcoatings.

The po1y-dihydronorpolycyclopentadienyl esters of a polycarboxylic acidmay be represented by the general formula:

wherein R. and n have the same significance as above and m is a numberfrom zero to three, inclusive.

While in the above examples essentially pure dicyclopentadiene or thealcohol derived therefrom by addition of water and rearrangement to thenorcyclopentadienyl system is used, there may be used with similarresults higher polycyclopentadienes or mixtures of dicyclopentadiene andhigher crystalline polycyclopentadienes having two double bonds permolecule. There may be prepared mixtures of crystalline di-, tri-,tetra-, and penta-cyclopentadiene having two double bonds and one tofour endomethylene cycles per molecule. These undergo the sameesterifying reactions as pure dicyclopentadiene. Further details of thebehavior of these polycyclopentadienes are given in the patentapplication. The polyesters of the varioushydroxydihydronorpolycyclopentadienes of the type aforesaid all have thedrying properties above described and are useful in coatingcompositions.

F'rom'the foregoing, it can beseen that the dihydronordicyclopentadienylpolyesters of organic polycarboxylic acids are unique and valuablematerials. They are particularly useful as varnishes or lacquers, eitheralone or with siccatives. They may be mixed in compositions with dryingor semi-drying oils, alkyd resins, and other filmeforming materials.They may be blown and bodied to a viscous state. They may be mixed withother autoxidizable derivatives from pol'ycyclopentadiene, including theesters of hydroxydihydronordicyclopentadiene and unsaturated higheraliphatic acids which are claimed in copending application Serial No.526,312, filed on even date. 1

I claim:

1. As a new compound, a polydihydronorpolycyclopentadienyl ester of apolybasic organic carboxylic acid, said ester being the acid-catalyzedaddition-rearrangement product of a polybasic carboxylic acid and acrystalline polycyclopentadiene havin two double bonds and one to fourendomethylene cycles per molecule, said es ter being furthercharacterized by having each carboxylic ester group attached to aterminal cycle from the rearranged polycyclopentadiene at a secondarycarbon atom thereof, the opposite terminal cycle thereof being afive-membered ring containing one olefinic linkage.

2. Asa new compound, a polydihydronordicy clopentadienyl ester of apolybasic organiccarboxylic acid, said ester being the acid-catalyzedaddition-rearrangement product of a polybasic,

carboxylic acid and dicyclopentadiene, said ester being furthercharacterized by having the carboxylic ester groups attached to aterminal cycle from the rearranged dicyclopentadiene at a secondarycarbon atom thereof, the opposite terminal cycle thereof being aflve-membered ring containing one oleflnic linkage.

3. As a new compound, a di-(dihydronordicyclopentadienyl) ester of adicarboxylic organic acid, said ester being the acid-catalyzedadditionrearrangement product of a dicarboxylic acid anddicyclopentadiene, said ester being further characterized by having eachcarboxylic ester group attached to a terminal cycle from the rearrangeddicyclopentadiene at a secondary carbon atom thereof, the oppositeterminal cycle thereof being a five-membered ring containing oneoleflnic linkage.

4. As a new compound, the di-(dihydronordicyclopentadienyl) ester ofmaleic acid, said ester being the acid-catalyzed addition-rearrangementproduct of maleic acid and dicyclopentadiene. said ester beingcharacterized by having each carboxylic ester group attached to aterminal cycle from the rearranged dicyclopentadiene at a secondarycarbon atom thereof, the opposite terminal cycle thereof being afive-membered rin containing one olefinic linkage.

5. As a new compound, the di-(dihydronordicyclopentadienyl) ester ofsebacic acid,.said ester being the acid-catalyzed addition-rearrangementproduct of sebacic acid and dicyclopentadiene, said ester beingcharacterized by having each carboxylic ester group attached .to a,terminal cycle from the rearranged dicyclopentadiene at a secondarycarbon atom thereof, the opposite terminal cycle thereof being afive-membered ring containing one olefinic linkage.

6. As a new compound, the di-(dihydronordicyciopentadienyl) ester ofphthalic acid, said ester being the acid-catalyzedaddition-rearrangement product of phthalic acid and dicyclopentadiene,said ester being characterized by having A. BRUISON.

